Fermilab Experience Joshua Louis
Dec 15, 2015
Introduction The goals of Fermilab's TRAC program:
To provide outstanding science, mathematics, computer science, and technology teachers with professional scientific, engineering, or technical experiences through summer research opportunities.
Increased awareness and understanding of cutting-edge science and technology obtained by the teacher can be transferred back to the classroom.
http://ed.fnal.gov/interns/programs/trac/
Liquid Argon R&D What is being developed?
Liquid Argon Purity Demonstrator (LAPD) Liquid Argon purity must be demonstrated before
neutrino research begins
Liquid Argon Purity Demonstrator Goals of LAPD
The primary goal of the LAPD is to test if required electron drift-lifetimes for a Time Projection Camber (TPC) can be achieved without evacuation in an empty vessel
An additional goal of LAPD is to understand how to scale the cryogenics system to a multi-kiloton detector.
Liquid Argon Purity Demonstrator Achieving Purity allows electrons to drift!
Purity is defined as: 30 ppt equivalent oxygen contamination
Why do we need this degree of purity? Other molecules such as 02 & H2O interfere with drift
Without purity no neutrinos can be detected
Liquid Argon Purity Demonstrator If the correct level of purity exists this is what you
should see:
The observed tracks are a result of neutrinos indirect interactions with liquid argon electrons Length, spin, & intensity all guide scientists to different
particles
My Contributions Three Primary Roles
Cryogenic Temperature Expansion Testing Trigger Counter Characterization Cryogenic Temperature Resistor Testing
Secondary Role Student of all things Fermilab
Cryogenic Temperature Expansion (CTE) Identify an Epoxy which could withstand liquid
nitrogen/argon temperatures and not be compromised Early testing revealed cracks in the epoxy which
held copper wire to various components
Cryogenic Temperature Expansion (CTE) This work included:
Wrapping the g-10 board in wire Mixing and applying several different epoxies to
the g-10 board
Cryogenic Temperature Expansion (CTE) This work included:
Wrapping the g-10 board in wire Mixing and applying several different epoxies to
the g-10 board Testing the thermal expansion of epoxy samples
Cryogenic Temperature Expansion (CTE) Results
Stycast 2850 closely aligns with thermal expansion of G-10
Additional cryogenic epoxies have been recommend for further study
3M 2216 - Grey 3M 2216 - Amber Stycast 2850 G10
Length (mm) 108.01 108.20 112.93 102.55
Thermal Expansion (mm) 1.088 1.562 .464 .329
Calculated Expansion (∆L/L)
4.56e-5 6.53 e-5 1.86 e-5 1.45e-5
0 5 10 15 20 25 30 350
0.1
0.2
0.3
0.4
G10 Transverse Ex-pansion Coefficent
Time (min)Mate
rial Expansio
n (
mm
)
0 5 10 15 20 25 300
0.1
0.2
0.3
0.4
0.5
Sycast 2850ft Expansion After Curing
Time (min)Mate
rial Expansio
n (
mm
)
Trigger Counter Characterization Get rid of any light leaks which lead to
interference with main signal, catalog characteristics, and label counters This requires a great deal of electrical tape and
patience Each counter takes at least 3 hours to produce a
complete signal
Trigger Counter Characterization Learning the complexities of the oscilloscope
18 trigger counters were processed
Trigger Counter Characterization What are trigger counters used for?
In order to trigger scan and provide the third dimension (time)
Beam
Cryogenic Resistor Testing Measure the change in resistance when
introduced into a cryogenic environment 240 Resistors where soldered onto a semi-
conductive platform
Cryogenic Resistor Testing Each resistor was measured to ensure
acceptable changes in resistance and component resilience Wire harnesses were created in order to provide a
reasonable testing format
Cryogenic Resistor Testing Preliminary ResultsResistor Room Temperature Liquid Nitrogen - Trail 1 Room Temperature2 Liquid Nitrogen - Trail 2 Room Temperature3
1 101.4 107.69 101.34 107.68 100.36
2 100.29 106.72 99.37 105.68 99.49
3 102.5 108.51 101.68 107.48 101.56
4 98.13 105.62 97.24 103.59 97.22
5 101.5 107.82 100.43 106.8 100.4
6 99.16 105.42 98.85 104.97 98.28
7 100.3 106.4 99.39 105.47 101.67
8 98.8 104.75 97.88 103.81 97.83
9 101.85 107.89 100.86 106.91 100.79
10 103.23 109.48 102.61 108.51 102.22
11 103.43 109.84 102.43 108.84 102.42
12 98.33 104.05 97.44 103.27 97.43
13 98.4 104.91 97.57 103.45 97.53
14 99.62 105.59 98.65 104.74 98.63
15 103.12 109.24 102.16 108.29 102.41
16 98.53 104.61 97.66 103.81 97.64
Avg. 100.54 106.78 99.72 105.83 99.74
Standard Deviation 1.91 1.89 1.93 1.97 1.96
Min 98.13 104.05 97.24 103.27 97.22
Max 103.43 109.84 102.61 108.84 102.42
* Measured in GOHM 15 min soak 1 hour warm-up 30 min soak 30 min warm up
Program Take Away I can share with my students the excitement that
comes from scientific research I will strive to model curriculum in a way that
accurately reflects the process of scientific innovation as observed at Fermilab
I am now familiar with cutting-edge technologies and scientific endeavors
I have made connections within my community that will allow my students to see what pursuing a career in science and technology could look like
I have been affirmed in my calling to be a professional educator
Thank You Harry Cheung & Bjoern Penning – Program
Coordinators
Stephen Pordes & Hans Jostlein – Immediate Supervisors
The amazing technicians, engineers, and physicists at PAB
The staff at lab 6